Oil burner



Dec. 30, 1941. E RQY F DEMlNG 2,268,068

OIL BURNER Filed Dec. 5, 1938 LIV *,/4 INVENTOR.

ATTORNEYS v u l z5 M5' agi Patented Dec. 30, 1941 UNITED STATES PATENTOFFICE 7 Claims.

This invention relates to oil burners for stoves, furnaces and otherheating devices, wherein is provided a fire box and combustion chamber,and

the primary object is to provide an oil burner having a specially formedpreheater through which is fed the supply of air supporting combustionand wherein is disposed one end of an oil supply duct that terminates ina conductor of a special nature, to the end that the oil introduced iskept below a predetermined or adjusted temperature and so thatvaporization might not occur until immediately before combustion.

A yet further aim of this invention is the provision of an oil burnerhaving a preheater, a haine therein and means associated with saidpreheater and baille for introducing oil .to a point immediatelyadjacent to the zone of combustion without imparting heat thereto, tothe end that carbonization is reduced to a point where it will notharmfully effect operation and the eiliciency of the burner is raised.

Another important object of this invention is to provide an oilburnerfor cook stoves, heating stoves and furnaces that may be installedwithout greatly altering the construction of the fire boxes orcombustion chambers thereof, and which will operate after installation,in an eflicient manner which will insure operation without interferencefrom'carbon even when using crude oil.

A still further object of the invention is the provision of an oilburner of the aforementioned characterwherein is included a speciallyformed preheater having a baffle therein which acts upon the airsupporting combustion in such fashion as to direct it through paths oftravel best suited for the contemplated heat transfer.

A large number of minor objects of the invention will appear during thecourse of the following specification, referring to the accompanyingdrawing wherein:

Figure 1 is a vertical central section through a portion of a furnacehaving'an oil burner installed in the combustion chamber thereof, whichburner is made to embody the present invention.

Fig. 2 is a horizontal sectional view taken on line II--II of FIZ. 1.

Fig. 3 is an enlarged fragmentary detailed ver-v tical sectional viewthrough a portion of the pan and plate assembly.

Fig. 4 is a detailed elevational view of a conductor embodying amodified form of the invention; and,

other form of conductor which extends between the oil supply tube andthe underlying pan.

Designers of oil burners have heretofore been particularly concernedwith the problem of creating an oil burner which would operate withoutthe' formation of carbon to the extent of causing interference with itsoperation. This problem has been connected with the necessity and desireto use a low grade hydrocarbon that would vaporize sufficiently tomaintain a constant flame in the zone of combustion.

One of the most difficult factors in creating oil burners that wouldburn a cheap grade of oil and yet operate eiliciently without harmfulformation of carbon, was to maintain the column of oil being fed to theburner at a temperature where vaporization could not occur untilimmeditely prior to flashing.

The combination of parts shown in the accompanying drawing, has beenfound to be satisfactory and therefore, the illustrated embodiment isthe preferred form which will be de- Fig. 5 is a detailed elevationalview of still an` 55 The ordinary furnace 8 having a shell I0 within`its outer Jacket I2 is usually supplied with a door Il, which may beutilized when installing the burner. vA passageway i6 connects theconventional stack so that gases and other objectionable products ofcombustion may escape.

In place of the grate, which is usually at the bottom of the combustionchamber i8 of furnace 8, itis desirable to install a solid plate 28 thatcarries pan 22, having upwardly extending continuous side ange 24 sothat the oil may be held therein when the burner is generated, or in theevent oil'should reach the burner without the possibility of burning.

Pan 22 has an apertured boss 26 at the center thereof which isinternally threaded, as shown in Fig. 3.

A frusto-conical plate 28 is mounted upon boss 26 at the center of pan22 so that any oil reaching the upper face thereof, will be directedinto the pan. This plate 28 is provided with a center internallythreaded bore 30 into which is projected nipple 32 which is externallythreaded so that it enters the openings in the pan and plate as shown inthe detail.

A downwardly directed, externally threaded pipe section 34 depends belowpan 22 and is provided With a cap 36 against which may rest one end ofconductor 38 when the type shown in Figs. 1 and 3 is employed. Thisconductor 38 is in the nature of a smooth rod having threads 40 thereonalong a portion of its length. Spacing nuts-42, threaded onto conductor28, have an external contour similar to the internal contour of nipple22 and pipe section 34; so that conductor 38 is held in a verticalposition when the parts are in the assembled relation.

The hollow preheater 44 is composed of a lower casting 46 and an uppercasting 48, the former being provided with an outlet port I0, while thelatter has an inlet port v52 in the upper wall thereof. These ports 50and 52 are in opposed relation when castings 48 and 48 are together, asshown in Fig. 1. Lower casting 48 has a plurality of fins 54, each ofwhich has a portion thereof exteriorly thereof of the preheater 44" anda portion on the inner side thereof. The portions of ilns 54 inside oflower casting 48 are made to support baille member 58 which has a hollowtubular, elongated boss 88 extending to each side thereof at its axis.This boss 58 receives one end of koil supply tube 80 and the boss islong enough to circumscribe a portion of tube 80 near the end thereofand a substantial portion of the length of conductor 38 near the en dwhich is projected into tube 60.

,The internal diameter of boss I8 should be sufficient to permit a smallamount of air to pass downwardly between the inner face thereof and.the'outer faces of tube 80 and conductor 38, Inlet port 52 is incommunication with an air supply duct 62 that extends to a point outsidethe furnace shell I0. Air is fed to supply duct 82 through any suitablelconnecting pipe 6l that may receive air from a.` blower, not here shown,or which may terminate at any point exteriorly of the furnace, merelyfor the purpose of admitting air to duct 62.

has been employed. and when oil escapes from the end of tube 80, it willflow downwardly by gravity over the outer surface of the links of chain80, to a point where vaporization occurs. The links of chain 80 have alimited amount of their surfaces in direct contact and therefore. heatexchange is discouraged, especially since ali` is passing around thelinks to further break up a direct path of travel for heat units.

In the operation of the oil burner, it is obvious that fuel oil is fedthrough tube 80 and lthat as it is being directed to the inner end oftube 68. a cooling effect is had thereon because of the relation of tube8| and duct 62. As the air approaches the zone of combustion, above.plate-28, it is quickly heated by contacting the ated to be directedoutwardly around the faces v burner.

It is notable that pipe 60 extends along duct 62y in spaced relation tothe side wallsthereof and when air is passing to the burner to supportcombustion, it implnges and sweeps along the outer face of tube 80 tomaintain the oil therein at a temperature below that permittingvaporization. Tube 60 is connected to any suitable source of oil supplythrough the medium of a pipe 66 and the conventional control valve 68may be used if desired.

l 1o and gas is to be used to maintain this puoi;

light in an operative condition, all as is known in the art. Y

An overflow pipe 'I2 extends outwardly from within furnace 8 from apoint within pan 22 so that if the burner should be extinguished for anyundesirable reason, the collecting oil will be drained from pan 22. Ifdesired, the oil escaping through pipe 12 may be used to :automaticallycut off the supply of oil through tube 60, in a well-known manner. y

The oil entering the burner through pipe 8p is conveyed along the outersurface of conductor 38 and since it is important to keep the oil withintube 60 as cool as possible, the formation of conductor 38 may bealtered to further insure that heat will not be transferred throughconductor 38.

Figs.q4 and 5 illustrate different ways oi: constructing the conductorwhich has before been indicated by the numeral 38.

In Fig. 4 the conductor 80 is in the nature of an ordinary rod aroundwhich has been spirally wound a wire 82, which directs the ow of oil ina downward spiral path until vaporization occurs.

The conductor 90, illustrated in Fig. 5, is of a different type in thatan ordinary link chain The upper face of plate 28 is constantly swept bythe incoming air and the zone of combustion is defined by the edge oflower casting 46, which forms outlet port 50 and plate 28.

The principles embodied inthe oil burner illustrated herewith and abovedescribed, may be built into burners having different physicalcharacteristics than that embodying the preferred form, and it isobvious to one skilled in the art that smaller oil burners made in adifferent manner,v may be constructed for use in smaller heatingstoves,jcooking ranges,l and domestic cook stoves.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

1. In an oil burner of the character described, I

a pan adapted to be positioned in the iire box of a stove or the like; ahollow air preheater above the pan, provided with an outlet port in thebottom thereof above said pan and an inlet port in the top thereof; anair supply duct in communication with the inlet port of the preheaterextending to a point exteriorly of the lire box; an oil supply tubewithin the air duct having one end within the preheater above the outletport and spaced above said pan; a lconductor for the oil bridging thespace betweenv the oil supply tube and said pan, said conductor beingformed to receive oil from the oil supply tube and convey the oil towardthe pan along the outer surface thereof; a baille within the preheater;and a plurality of fins integral with the preheater, said fins havingportions thereof within the preheater adaptedto operably carry thebaille in spaced relation with the inner face of the preheater, thelower wall of .said preheater, said bame and the said portions of thefins in the preheater combining to create a number of radially disposedpassages around the conductor. 2. In an oil burner of the characterdescribed, a pan adapted t0 be positioned in the nre box of aA stove orthe like; a hollow air preheater above the pan, provided with an outlet.port in the bottom thereof above said pan and an inlet port in the topthereof; an air supply duct in communication with the inlet port of thepreheater extending to a point exteriorly of the fire box; an oil supplytube within the air duct hav ing one end within the preheater above theoutlet port and spaced above said pan; a conductor for the oil bridgingthe space between the oil supply tube and said pan, said conductor beingformed to receive oil from the oil supply tube and convey the oil towardthe pan along the outer surface thereof; a baille within the preheater;

and a plurality of fins integral with the preheatthereof, whereby air iscaused to impinge upon the liquid fuel from the time it leaves the saidend of the supply means and throughout the time of vaporization.

5. In an oil burner of the character described having a combustionchamber, a hollow preheater for supplying air to said chamber providedwith an air inlet port and an air outlety port; a conduit for supplyingliquid fuel to the burner having one end above the-outlet port; aconductor extending from the said end of the conduit into the zone ofcombustion to conduct liquid by gravity along its exterior surfacetoward said zone of combustion; a tubular enclosure having an insidediameter greater than the outside diameter of the conductorcircumscribing a substantial portion of the length of said con- 3. In anoil burner of the character described a hollow preheater adapted to bepositioned in a fire box of a stove or the like and provided with anoutlet port in the bottom thereof and an inlet port in the top; meansfor supplying liquid fuel to the burner having one end within thepreheater above the outlet port; means for delivering air to the inletport from outside the re box; a baille within the preheater formed tocooperate with the walls of the preheater in directing air from theinlet port to the outlet port through a circuitous path whereby to heatthe air;` a conductor depending below the end of said liquid fuel supplymeans and adapted to convey the liquid fuel toward the zone ofcombustion and the outletport of the preheater; a tubular bosscircumscribing the said conductor and positioned to direct a portion ofthe air from outside the fire box, downward along the conductor tomaintain the temperature of the liquid fuel below the flash pointthereof while in said boss and means for directing the flamesvofcombustion outwardly below the preheater.

4. In an oil burner of the character described a hollow preheateradapted to be positioned in a fire box of a stove or the like andprovided with an outlet port in the bottom thereof and an inlet port inthe top; means for supplying liquid fuel to the burner having one endwithin the preheater above the outlet port; means for delivering air' tothe inlet port from outside the iire box: a baule within the preheaterformed to cooperate with the walls of the Dreheater in directing airfrom the inlet port to the outlet port through a circuitous path wherebyto heat the air; a conductor depending below the end of said liquid fuelsupply means and adapted to convey the liquid fuel toward the zone ofcombustion and the outlet port of the preheater; a tubular bosscircumscribing the said conductor and positioned to direct a portion ofthe air from outside the fire box, downward along the conductor tomaintain the temperature of the liquid fuel below the'ash ductor to forma space around the latter for the passage of air; and a balile on theexterior of said tubular enclosure to deflect the remaining portion ofthe air outwardly therefrom, whereby a small portion of unheated air ispassed along said conductor to maintain, the liquid fuel thereon belowthe flash temperature.

6. In an oil burner of the character described having a combustionchamber; a hollow preheater for supplying air to said chamber providedwith an inlet port and an outlet port; a conduit for supplying liquidfuel to the burner having one end above the outlet port; a conductorextending from the end of said conduit into the zone of combustion toconduct liquid by gravity along its exterior surfaces toward said zoneof combustion; a tubular enclosure having an inside diameter greaterthan the outside diameter of said conductor, said tubular enclosurecircumscribing a substantial portion of the length of said conductor toform a space around the latter for the passage of air whereby a smallportion of unheated air is passed along said conductor to maintaintheliquid fuel thereon below the flash temperature; a baffle on theexterior of said tubular enclosure to direct the remaining portion ofthe combustion air through a path whereby it is heated.

7. In an oil burner of the character described having a combustionchamber; a hollow preheater for supplying air to said chamber providedwith an inlet port and an outlet port; a conduit for supplying liquidfuel to the burner having one end above the outlet port; a conductorextending from the end of said conduit into the zone of combustion toconduct liquid by :gravity along its' exterior surfaces toward said zoneof combustion; a tubular enclosure having an inside diameter greaterthan the outside diamete' of said conductor, said tubular enclosurecircumscribing a substantial portion of the length of said conductor toform a space around the latter for the passage of air whereby a smallportion of unheated air is passed along said conduca tor to cause air toimpinge upon the oil as the point thereof while in said boss; and meansfor directing the flames of combustion outwardly below the preheater,said conductor being formed to convey the fuel along theexterior surfacesame is vaporized; and a baille on the exterior of said tubularenclosure to direct the remaining portion of the combustion air througha path whereby it is heated. i

LE ROY F. DEMING.

